Installing Outbound

Downloading Outbound, moving it to Applications, and the setup steps that let macOS filter your connections.

Outbound 1.3.0 · Updated 24 October 2026

Installing Outbound is a download, a move to Applications, and a short setup that asks macOS for three permissions. Setup explains the filter prompts before you approve them.

Requirements

macOS 14 or later. That is the minimum the app is built for; the compatibility page lists the supported versions and the features that need a newer macOS.
An Apple silicon or Intel Mac.
Your password or Touch ID: macOS may ask for it when you approve the network filter.

Download Outbound from outboundfirewall.com.

First launch: the licence

The first thing a new Outbound shows is the licence screen, before any setup: paste the key from your purchase email and click Activate. If you have not bought one yet, the Buy Outbound link opens the pricing page. Setup and the network filter come after. See Trial and licence.

Moving Outbound to Applications

The network filter can only be installed from the Applications folder, so setup checks where your copy lives. If the copy is somewhere else, the setup window explains the problem and offers Move to Applications; Outbound copies itself there, quits the copy you opened, and reopens from Applications. When it replaces an older copy in Applications, the button says Updating… while it works. If Applications already contains the same or a newer build, Outbound opens that copy instead. A disk image is ejected after the installed copy starts. If Applications is not writable, use Finder to move the app with administrator approval.

Setup also handles these situations:

A copy that is not signed for installing filters: get a fresh copy from wherever you got Outbound, or open the signed copy already in Applications.
A copy macOS opened from a temporary, protected location: move it to Applications first.
A copy that has been renamed: the app needs to be named Outbound and live in Applications so macOS can find its filter. Setup offers to copy it with the correct name.

The setup steps

Setup walks through nine pages: welcome, choosing a mode, trust, known trackers, performance, installing the filter, allowing filtering, background access, and ready. A speaker button at the top right turns setup’s music and sounds off.

The choices you make in setup, such as the mode, what to trust and which trackers to block, are only staged as you go. Nothing is saved until you click Finish Setup on the last page. The three macOS permissions are different: macOS records those as soon as you approve them. If you close setup before finishing, Outbound asks “Discard setup choices?” with Keep Setting Up and Discard Choices; discarding leaves your settings as they were.

Outbound setup, Welcome: apps on the left connecting through Outbound to sites on the right, one tracker stopped, and See, Decide and Private — Example data.

Choose how Outbound works. The three modes are Learn (allow and record new connections), Ask (ask before an app connects somewhere new) and Strict (block anything you haven’t allowed). Learn is marked Recommended. Continuing with Strict asks whether you really want to start there, with Start with Learn as the alternative. In Ask and Strict, an Allow the apps I already have checkbox offers to trust the signed apps already in Applications; it is ticked unless you untick it. If your organisation manages the mode, the page says “Your organization chooses this mode.” See Operation modes.

Outbound setup, Choose how Outbound works: Learn, Ask (selected, with Allow the apps I already have) and Strict, above an example question from Finder — Example data.

Trusted by default. “Choose familiar services to trust. You can review these choices later.” Four switches for familiar services, each with an arrow that unfolds examples: macOS services (software updates, local network discovery, certificates, push notifications, background downloads), iCloud & Apple services, Apple apps (Safari, Mail and Music), and Apps you already have (the signed apps in Applications, counted while setup scans). Checkboxes below them cover three more groups: Local network, VPN apps and Simulator processes. Then Block ads and trackers offers Peter Lowe’s list, about 3,500 ad and tracking servers, refreshed daily, as a starter blocklist. Trusted connections are allowed without asking; you can change all of it later. See Trusted apps and Blocklists and rule groups.

Outbound setup, Trusted by default: macOS services, iCloud and Apple services and Apple apps on; apps you already have and blocking ads and trackers off — Example data.

Block known trackers. “Outbound blocks the analytics and advertising servers apps report to wherever that leaves the app working; servers that might affect an app stay your choice, app by app.” Blocking is selected; you can choose not to. Only the first setup shows this page. Later, the same choice is in Settings › Telemetry. If your organization manages it, the page says “Your organization chooses this.”

How Outbound runs on this Mac. A performance choice: Automatic (Recommended), Always efficient or Always full quality. Protection is the same on every setting; this only governs the visuals. See Performance and memory.

Install the network filter. Outbound asks macOS to install its system extension. macOS shows an alert titled System Extension Blocked (macOS 14 through 26) or “Outbound” would like to use a new network extension (macOS 27 and later). Click Open System Settings, not OK; nothing is lost if you click OK by mistake, the page offers the button again. The page walks you through the switch to turn on:

macOS 27 and later: open the Network Extensions list, turn on Outbound.app (listed as Outbound Network Filter), click Done, and approve with Touch ID or your password if asked.
macOS 15 and 26: open General › Login Items & Extensions, click the ⓘ next to Network Extensions near the bottom, and turn on Outbound Network Filter.
macOS 14: open Privacy & Security, scroll to Security, and click Allow for the Outbound system extension.

While macOS thinks about it the page says it is waiting, and it moves on by itself when the approval lands. A guide floats beside System Settings. It confirms approval when macOS reports it and returns you to Outbound. Its close button hides the guide. If the request sits unanswered for 30 seconds, the page offers Install Filter again and suggests a restart if it keeps happening.

Outbound setup, Install the network filter: why Outbound asks, what happens if you skip it, what it never sees, and what macOS will show next, with an Install Filter button — Example data.

Allow network filtering. The prompt is titled “Outbound” Would Like to Filter Network Content. Choose Allow; the setup page even shows a picture of this prompt with the right button marked. If you chose Don’t Allow, turn Outbound on in System Settings › Network › Filters (macOS 14 through 26) or Network › VPN & Filters (macOS 27 and later). When enabling filtering fails, the page offers Open Network Settings and Ask Again. If the extension is no longer installed, Return to Filter Setup takes you back. The page continues once filtering is on.

Outbound setup, Allow network filtering: the macOS question with Allow marked as the choice, why Outbound asks and what happens if you skip it — Example data.

There when you need it. The last permission lets Outbound run in the background: System Settings › General › Login Items & Extensions, and turn on Outbound under Allow in the Background (macOS 14 through 26) or Outbound.app under Background App Activity (macOS 27 and later). The page links straight there and numbers the two steps. Without it, your rules still apply, but nothing asks you about new connections and the menu bar item is gone while the window is closed.

Outbound setup, There when you need it: why the background agent runs, what happens without it, and the steps in Login Items, with an Enable Background Access button — Example data.

You’re ready to go. “Review your choices. Finish applies them together.” A checklist line confirms all three permissions: Filter running, Filtering on, Background allowed. Below it, a summary lists every choice you made, grouped under Protection (the mode, known trackers, the ads and trackers blocklist and rule groups) and Extras (performance and sound). Each choice has a Change link that takes you back to its page. Click Finish Setup to save them all at once, or Show Me Around to save them and open a short tour on the Overview. A small passport card is issued once, on the first completed setup.

If a permission changes before you finish, the page reads “Let’s finish setting up”: “A required permission has changed. Complete the remaining steps to turn on Outbound.”

After setup, Edit › Undo can undo the choices Finish Setup saved, as long as nothing has changed them since. To look at your setup choices again later, choose Help › Review Setup…. It opens the same pages with your current choices, and again saves nothing until you finish.

Outbound setup, You’re ready to go: filter running, filtering on and background allowed, a map of 29 connections in 9 countries, the first connections, and Show Me Around and Open Outbound — Example data.

When installation goes wrong

If the filter cannot install, setup translates the error into these messages:

Message	What it means
macOS hasn’t answered yet. Choose Install Filter to ask again. If it keeps waiting, restart your Mac: older copies of the filter may be waiting to be removed.	The activation request went unanswered for 30 seconds.
macOS couldn’t install the filter. Restart Outbound and try again.	The activation failed with a general error.
This copy of Outbound isn’t signed for installing filters. Use the copy in Applications or download Outbound again.	The copy is unsigned or wrongly signed.
Move Outbound to the Applications folder, then open it there to install the filter.	The app is outside Applications.
The network filter is missing from this copy. Install a fresh copy of Outbound.	The extension is not in the bundle.
This copy’s network filter is incomplete. Install a fresh copy of Outbound.	The extension is incomplete.
macOS found more than one copy of the filter. Quit other copies of Outbound and open the copy in Applications.	Another copy is installed or running.
macOS doesn’t recognize this filter. Install the latest version of Outbound.	The extension’s identity is unknown to macOS.
macOS couldn’t verify this copy of Outbound. Download a fresh signed copy.	Signature verification failed.
macOS couldn’t validate the network filter. Install a fresh copy of Outbound.	The extension failed validation.
Your Mac’s security policy doesn’t allow this filter. Contact your administrator.	The Mac’s security policy rejects the filter.
Installation was canceled. Choose Install Filter to try again.	The request was cancelled.
Another installation replaced this request. Wait for it to finish, then try again.	A newer activation took over.
macOS needs your permission. Open System Settings and approve Outbound Network Filter.	The approval is waiting in System Settings.

If a newer Outbound replaces an older filter, macOS swaps same-team filters without asking again; when a restart is needed to finish the swap, setup says “Restart your Mac to finish updating the filter, then reopen Outbound.”

After setup

You can see all three permissions, what each one lets Outbound do, and what stops working without it, any time in Settings › Permissions. If something misbehaves later, start at Something not working?.